This invention relates to surgical clips useful for ligating vessels in the human body and to cartridges useful for holding hemostatic clips.
During surgical procedures it is necessary to occlude blood vessels, and while several means are available, the usual method is to clamp such vessels with hemostatic clips. A very successful clip design is described in U.S. Pat. No. 3,363,628 and sold by Edward Weck Incorporated under the trademark HEMOCLIP.RTM.. Such clips are applied with an automatic applier or a hand held forceps-type clip applier which deforms an open clip around the vessel to clamp it shut. In particular, the hand held forceps-type appliers have specially shaped jaws into which individual clips are introduced and then applied to clamp a vessel.
Various packaging means have been used in an effort to supply clips in a manner that is convenient to the surgeon and which involves a minimum of manipulation by the surgeon in picking up a clip in the applier so that it is firmly held until the surgeon has applied it to the particular vessel. Most clips are packaged in some form of cartridge which can be loaded sterilized in a pouch. In general, the cartridges support individual clips in separate compartments. Such cartridges must provide some means of retaining the clips in place until picked up by the clip applier, and these retaining means often present difficulties or inconvenience to the surgeon who is using the clips.
U.S. Pat. No. 4,344,531 discloses a class of hemostatic clip cartridges which automatically move a plurality of pre-formed U shaped or V shaped hemostatic clips, which have been pre-loaded into the clip cartridge, to provide individual hemostatic clips serially at an open delivery station of the cartridge. A surgeon is able to obtain an individual clip in a convenient manner from the same location each time a clip is needed without hindrance from the kind of retaining means associated with compartmented cartridges. In addition, the surgeon is not required to search for a compartment containing a clip, but knows that he can always obtain a clip from the single delivery station of the automatic feed cartridge.
Even these automatic feed cartridges have problems in that clips like those described in U.S. Pat. No. 3,363,628 loaded serially in a row within the cartridge are forced into contact with one another at the curved outer surfaces of the ridges of the clips by a slider and spring arrangement designed to exert a force on the row of clips longitudinally along the cartridge in the direction of the delivery station. Because of the clearances allowed within the cartridges and the curved nature of the contacting surfaces, the clips become misaligned and may jam within the cartridge. Also, when the clips are first loaded into the cartridge a force larger than that which is necessary to move the row of clips is exerted on the clips by the variable force compression spring. This adds to the likelihood that the clips being compressed together will jam. Hence, a new automatic clip cartridge and/or clip design is desired to overcome the aforementioned problem of jamming.